Polyformals based on Bisphenol-A were first reported by Barclay, U.S. Pat. No. 3,069,386. They were made by reaction of the anhydrous disodium salt of Bisphenol-A with one equivalent of bromochloromethane in dimethyl sulfoxide. More recently, Hay, et al, in a recent presentation entitled "Synthesis of New Aromatic Polyformals", at the 1982 Fall ACS Meeting in Kansas City, Mo. addressed their manufacture.
German Offen. No. 2,738,962, May 11, 1978, based on U.S. application Ser. No. 739,562, filed Nov. 8, 1976, now U.S. Pat. No. 4,124,875, describes the manufacture of aromatic polyformal resins of which the units have structure --OROCH.sub.2 -- wherein R is an arylene of 6 to 30 carbon atoms and the resin has an intrinsic viscosity of about 0.3 dl/g, measured in chloroform at 25.degree. C. They are prepared specifically from Bisphenol-A, an excess of methylene halides, and an alkali metal hydroxide.
German Offen. No. 2,819,582, published Sept. 27, 1979, based on U.S. application Ser. No. 889,393, filed Mar. 23, 1978, now abandoned describes flexible, film-forming polyformals having the repeating structure: ##STR3## which are manufactured by the reaction of one mole of Bisphenol-A and at least a stoichiometrically equivalent amount of methylene halide in the presence of at least a stoichiometrically equivalent amount of an alkali metal hydroxide and a phase transition catalyst with or without a dipolar aprotic solvent. This patent publication appears to correspond to the Hay et al ACS publication.
There appears to be no prior art directed to the employment of such polyformals with other resins, in particular with styrene copolymers and vinyl chloride as polymers, herein set forth.
The aromatic formals of this invention are described in copending application Ser. No. 485,947, now abandoned commonly assigned, filed on even date herewith.